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Biomedical subjects

K Tada

Publications and source records attributed to K Tada.

At least 325 records · Page 18Linked to original sources
PubMed1988

Analysis of glucose-6-phosphate translocase and hexose-6-phosphate phosphohydrolase, the two obligatory components of microsomal glucose-6-phosphatase system, in rat liver.

A membrane filter procedure developed by Igarashi et al. (1984) for the measurement of glucose 6-phosphate uptake by the microsomes has been demonstrated to be a good method for assaying glucose-6-phosphate translocase, an obligatory component of the microsomal glucose-6-phosphatase system. When glucose-6-phosphate translocase was assayed in developing and diabetic rat livers independently of hexose-6-phosphate phosphohydrolase, another obligatory component of the glucose-6-phosphatase system, the two activities were found to undergo alterations, whose profiles, however, were quite distinct from each other. The profile of the microsomal glucose-6-phosphatase activity resembles the profile of the phosphohydrolase activity rather than that of the translocase activity, suggesting that the phosphohydrolase may be rate-limiting at least under these conditions. AH-109A, a strain of transplantable rat ascites hepatoma, was found to lack both glucose-6-phosphate translocase and hexose-6-phosphate phosphohydrolase activities.

Aging↗
PubMed1988

Gentamicin dosing and pharmacokinetics in low birth weight infants.

Monitoring of serum gentamicin concentrations and one-compartment pharmacokinetic analysis were performed in 41 preterm low birth weight infants (20 with birth weight of less than 1,500 g and 21 with birth weight of greater than or equal to 1,500 g) in the first week of life. Our dosing regimens, which were 2.0 mg/kg every 24 hr for the less than 1,500 g group and 2.0 mg/kg every 12 hr for the greater than or equal to 1,500 g group, successfully achieved the desired peak (4-8 micrograms/ml; 87.8%) and trough (less than or equal to 3 micrograms/ml; 97.5%) concentrations on the 4th day of treatment. In a one-compartment pharmacokinetic analysis, a large intersubject variability of pharmacokinetic parameters were observed on the 1st day of treatment. When we compared the parameters of the 1st day with those of the 4th day, apparent decreases in Vd and TBC were observed. The mean values for TBC and T1/2 or Kd of the two birth weight groups were significantly different from each other on the 4th day of treatment, suggesting a less maturity of renal functions in the less than 1,500 g group. The modified method of Sawchuk and Zaske was proven impractical in predicting steady-state serum concentrations because of an underestimation probably caused by the dramatic alteration of Vd due to a diuresis soon after birth. Based on these results, we recommend the above-described dosing regimen and emphasize the importance of a close monitoring of serum gentamicin concentrations and toxicities, instead of the individualized dosing approach in low birth weight infants in the first week of life.

Bacterial Infections↗
PubMed1988

Direct determination of the blood concentration of halogenated anesthetic agents by gas chromatography.

The direct determination by gas chromatography of blood levels of anesthetic agents has been difficult because of the water content of blood. In the present study, the method of Yokota et al. (1967) was modified by improving the packing materials of the column, the blood sample vaporizer and the flow-path during analysis. As a result, accurate and reproducible determination of halothane, enflurane and isoflurane dissolved in blood was achieved. With this system, blood in which halothane, enflurane and isoflurane had been dissolved could be analyzed without changing the column between samples. Moreover, each sample was prepared in less than 10 min, and more than 100 consecutive determinations could be made with excellent reproducibility. The coefficient of variation was less than 3.8%.

Chromatography, Gas↗
PubMed1988

Cervical spondylotic myelopathy in the aged patient. A radiographic evaluation of the aging changes in the cervical spine and etiologic factors of myelopathy.

Cervical spondylotic myelopathy among older individuals was investigated radiographically in 42 patients over age 60 years, and compared with those of younger patients. The cervical spine in the aged patients displayed dynamic canal stenosis in addition to static canal stenosis based on the aging process. Myelography and computed tomography-myelography showed multisegmental lesions (average: 3.0 lesions), that contributed to the various clinical features of myelopathy. The upper disc levels of C3-4 and C4-5 had a tendency to be involved in the aged patients, and the spinal cords were extensively compressed as compared with the younger patients. Disc protrusion, posterior osteophyte, and retrolisthesis, in addition to ligamentous entrapments were the primary etiologic factors of myelopathy. Morphologically, the high prevalence of cord atrophy was seen on computed tomography-myelography in the aged patients. This indicated severe pathologic changes in the cervical spinal cord, and its prognosis was considered to be poor.

Aged↗
PubMed1988

Nerve repairs for traumatic brachial plexus palsy with root avulsion.

Thirty-six patients with traumatic brachial plexus lesions and root avulsions were treated surgically between 1972 and 1986 and were followed for more than 24 months (average, 42.6 months). Neurotization of the musculocutaneous nerve with intercostal nerves or the spinal accessory nerve resulted in satisfactory elbow flexion in 21 of the 33 cases (64%). Combined nerve repairs (i.e., intercostal and spinal accessory neurotization of the terminal branch of the brachial plexus in combination with nerve grafts from the upper spinal nerves of the brachial plexus) created a useful function in at least one functional level of the upper limb for 11 of the 15 cases so treated. Nerve repairs resulted in stability of the shoulder and elbow function controllable with a sensible hand for patients with root avulsion injury of the brachial plexus.

Adolescent↗
PubMed1987

Anti-Purkinje cell antibody producing B-cell lines from a patient with paraneoplastic cerebellar degeneration.

Two patients with paraneoplastic cerebellar degeneration with anti-Purkinje cell antibodies are described. Using an avidin-biotin peroxidase complex method, serum anti-Purkinje cell antibody titers of these patients were 1:32,000 and 1:64,000, and the cerebrospinal fluid titers were 1:40 and 1:320, respectively. After extensive plasmapheresis together with radiation therapy and chemotherapy, the cerebellar symptoms of one patient ameliorated concomitantly with a reduced serum anti-Purkinje cell antibody titer. Four B-cell lines producing anti-Purkinje cell antibodies were established from one patient by Epstein-Barr virus transformation of peripheral lymphocytes. None of these antibodies reacted with peripheral T cells, although the serum anti-Purkinje cell activity of the patient was markedly reduced after absorption with purified human T cells. Thus, anti-Purkinje cell antibodies are apparently directed both to antigens unique to the cerebellar tissue and those shared by T cells.

Adenocarcinoma↗
PubMed1987

Cerebral glucose utilization in pediatric neurological disorders determined by positron emission tomography.

We measured local cerebral glucose utilization in 19 patients with Lennox-Gastaut syndrome (LG), partial seizures (PS), atypical and classical phenylketonuria (PKU), Leigh disease, and subacute sclerosing panencephalitis (SSPE), using positron emission tomography (PET). The mean values of regional glucose utilization in interictal scans of LG were significantly reduced in all brain regions when compared with that of PS (P less than 0.005). PET studies of glucose utilization in LG revealed more widespread hypometabolism than in PS. Two siblings with dihydropteridine reductase deficiency, a patient with classical PKU, and a boy with cytochrome c oxidase deficiency showed reduced glucose utilization in the caudate and putamen. A marked decrease in glucose utilization was found in the cortical gray matter of a patient with rapidly progressive SSPE, despite relatively preserved utilization in the caudate and putamen. The PET study of a patient with slowly progressive SSPE revealed patterns and values of glucose utilization similar to those of the control. Thus, PET provided a useful clue toward understanding brain dysfunction in LG, PS, PKU, Leigh disease, and SSPE.

Adolescent↗
PubMed1987

Partial ornithine transcarbamylase deficiency in females: diagnosis by an immunohistochemical method.

Females heterozygous for the X-linked urea cycle disorder, ornithine transcarbamylase (OTC) deficiency have a significant risk of developing hyperammonaemia. Diagnosis of this genetic defect in a proband is the essential starting point for family studies. By an immunohistochemical analysis of the liver specimens fixed in 10% formalin, we confirmed heterozygous status for OTC deficiency in two female patients, a 15-year-old girl and a 2-year-old girl, who died of hyperammonaemia. Since most affected males lack cross reactive materials (CRM), an immunochemical analysis should be useful for the diagnosis of most heterozygous females.

Adolescent↗
PubMed1987

Non-ketotic hyperglycinaemia: clinical and biochemical aspects.

Non-ketotic hyperglycinaemia is an autosomal recessive disorder of glycine metabolism characterized by elevated concentrations of glycine in plasma, urine and cerebrospinal fluid. The fundamental defect was found to lie in the glycine cleavage system. It is of significance that the major pathway for the catabolism of glycine was elucidated through the studies of hyperglycinaemia. The present knowledge about non-ketotic hyperglycinaemia is described in clinical and biochemical aspects.

Amino Acid Metabolism, Inborn Errors↗
PubMed1987

Regional cerebral metabolic rate for glucose in subacute sclerosing panencephalitis.

Regional cerebral metabolic rates for glucose (rCMRglc) were measured in two cases of subacute sclerosing panencephalitis (SSPE) with different clinical courses. A marked decrease in rCMRglc was found in the cortical gray matter of a patient with rapidly developing SSPE (3.6-4.2 mg/100 g brain tissue per min). However, the rCMRglc was preserved in the caudate and lenticular nuclei of the patient (7.7 mg/100 g per min). The rCMRglc in a patient with slowly developing SSPE revealed patterns and values similar to those of the control. The rCMRglc correlated better with the neurological and psychological status of SSPE.

Adolescent↗